Turns out there are punks everywhere. On Long Island, where writer-director Rob Weiss's promising debut film, "Amongst Friends," takes place, they're bored, rich creeps, making scores and running scams and small-time dope deals, mostly because they've got too much time on their hands. "We weren't stealin'," says Andy (Steve Parlavecchio), one of the film's boyhood gang of three and its narrator. "We were experimenting."

The area is called Five Towns, a cluster of mink-lined suburban ghettos where "rabbis are neighbors to gamblers, and the well-tended lawns of judges border the well-tended gardens of gangsters." Almost since birth, the movie's three main characters -- Andy, the little one and "the idea man" of the group, and the bigger, tougher Billy (Joseph Lindsay) and Trevor (Patrick McGaw) -- have prowled the streets together. And when we first see them (on scratchy super-8mm film) as kids in the early '80s, Weiss wants us to accept them as innocent children. (The Big Audio Dynamite song "Innocent Child" gives us a note in the soundtrack to that effect.) And their story, it soon becomes clear, is the chronicle of their corruption -- their fall from that blessed state into the real-life, grown-up world of crime.

As Andy tells it, their whole lives just sorta ... happened. Billy, who talks tough but seems a little twitchy and insecure, is the only one of the three who's really into crime as a career. Andy has been reduced to the status of errand boy, and Trevor just picks up some loose change here and there while he waits for his girlfriend, Laura, to graduate from high school.

One night Billy asks Andy to make a drop for him; Andy says yes, then cons Trevor into doing the job for him, so the bust that was meant for Billy goes to Andy and then to Trevor, who as a result gets to do a stretch in prison.

Weiss arranges this long line of dramatic dominoes and sets it up to tumble upon Trevor's return. The time now is the early '90s, and Andy is still a gofer for Billy, who's grown into a fairly powerful crook, and when Billy sees that his old friend Trevor has returned, he's not exactly happy. "Now long you's staying?" he asks by way of welcoming the guy who got busted in his place.

Though Trevor is the film's most sympathetic character, Billy is its most complex. Weiss directs with a sure sense of story and atmosphere and a nice ear for music -- the Mick Jones soundtrack sets a slightly dreamy, floating mood -- and he was smart not to fill us in too much on the motives behind Billy's actions. We're never sure, for example, if Billy knew he was going to be busted that night and tried to set up Andy for the fall. Or whether he was as surprised as Trevor was.

A third factor -- Trevor's girlfriend, Laura (played with exquisite simplicity by Mira Sorvino) -- further clouds the issue, especially when Trevor learns that Laura has been seeing Billy during his time in jail.

Structurally, Weiss's script is so sound that it almost seems to play out by itself. And the low-key, polyester criminality of these Long Island small-timers has the feel of a new world, of places we've never been and places we've never seen.

This is one of the great pleasures of moviegoing, and "Amongst Friends" at least gives us an intriguing tour of an unknown subculture. But somehow there's not enough depth in the conflicts Weiss has set up, and little vitality in the way he puts this world on display.

We feel this dullness of spirit most whenever a pair of fast-talking fat boys in matching designer sweats named Vic and Eddie (Frank Medrano and Louis Lombardi) show up to kick the movie into high gear for a few moments. They're like a rapping pair of Pillsbury Doughboys on a night out in Atlantic City. And when they leave, and we're forced to settle back in and watch as Billy systematically destroys both his old friends, the action is so programmatic that it hardly seems worth the effort.

Also, Weiss doesn't seem to have much of a feel for actors. Aside from small but potent contributions from Sorvino, Medrano and Lombardi, the cast is only passable at best and, at worst, a strange combination of strained and inert. As Billy, Lindsay fully exposes the gears of his performance; he shows us his acting, not his character. And Parlavecchio's Andy is simply tone-deaf -- a drawback for a film's narrator.

Thematically, the movie is about friendship and betrayal and loss of innocence, but Weiss's ideas are on the dully ironic level of the title. "Amongst Friends" would love to be a "Mean Streets" for the '90s, and its Long Island streets may be mean enough, but here they're barely semi-tough.